Engineers that cut corners, and engineer products that create RF energy that are not supposed to radiate anything but light, when during the design process these problems can be easily mitigated by proper application of bypass capacitors and inline choke filters just to save a few cents per unit should be taken out and horsewhipped.
These problems have reared their ugly heads because our regulatory agency's have in no way enforced the standards that were set long ago for incidental unintentional RF radiation. The invention and rise of the switching powers supply to supplant linear transformer based supplies in the last few decades to produce cheap lightweight and compact power supplies have become the norm.
Switching power supplies have totally taken over now, and most devices in my home have switching power supplies, and I have spent many hours and much money solving the problems they cause to radio reception. Most people don't know or care that their "chargers" and power supplies emit RF energy, but I do.
But to have a simple 12 volt LED light bar produce enough RFI to affect the Mobile broadcast receiver in a tractor is disgusting and totally uncalled for and unnecessary and would be easy to mitigate at the design level. It is much more difficult to "retrofit" anything than it is to design it correctly in the first place.
Yep, I have been KØUA since 1975. Congratulations on getting your Extra.